Liver disease

Question 1

Clinical signs of hepatic dysfunction

Answer 1

Lethargy/inappetance

Weight loss

Colic

Photosensitisation

Encelopathy

Diarrhoea

Jaundice

Oedma

Coagulopathy

Or none!

Question 2

Prognosis of liver disease

Answer 2

If signs then prognosis guarded

Question 3

Liver enzymes

Answer 3

AP - biliary
AST - hepatocellular, can go up in muscle disease
GGT - biliary, can also be elevated in GI disease
GLDH - hepatocellular

Question 4

Functional parameters of liver

Answer 4

Albumin
Globulins
Bile acids
Bilirubin
Urea

Question 5

Why performa liver biopsy

Answer 5

Confirms presence of liver disease

Guides treatment selection

Provides reliable estimate of prognosis

Question 6

When to perform a liver biopsy

Answer 6

Clinical signs

Clinical pathology results

One horse in herd has suspected liver disease, test herd mates

Question 7

When not to performa liver biopsy

Answer 7

Hepatic lipidosis - because liver may rupture

Colic - can induce transient liver insult

Question 8

Where to perform liver biopsy

Answer 8

Hip to horse

Scan dorsal to ventral in each intercostal space

Check from 15th to 10th ICS

Pause to watch lung

Check left and right sides of the horse

Measure depth of liver

Question 9

How many biopsy samples do you need to take to overcome inaccuracy

Answer 9

> 10 complete portal tracts need to be examined so 2 or 3 biopsies

Question 10

Potential complications of liver biopsy

Answer 10

Haemorrhage
Peritonitis/enterocentesis/colic
Pneumothorax/pleuritis

Question 11

Specific diagnoses that can be made from histopathological assessment of liver biopsy

Answer 11

Amyloidosis
Neoplasia
Marked eosinophilic infiltrate -> MEED
Septic cholangiohepatitis
Pyrrollizidine alkaloid toxicity
Haemosiderosis

Question 12

Septic cholangiohepatits

Answer 12

Look for neutrophilic portal infiltration on the report

rarely diagnosed

Question 13

Ragwort toxicity

Answer 13

Megalocytosis

Rare cause of liver disease in the UK

Avoid presumptive diagnosis - take biopsy

Question 14

Haemosiderin deposition

Answer 14

Look for deposition haemosiderin in a proportion of hepatocytes

Severe deposition (>50%): poor prognosis

Excess dietary iron is deposited as haemosiderin

Might cause outbreaks of hepatic insult

Horses are never iron deficient, but can get toxicity

Question 15

Chronic active hepatitis

Answer 15

Used to be more common

Look for mononuclear infiltrate in the portal areas (lymphocytes and plasma cells)

Aim of treatment is to reduce inflammation and risk of fibrosis development

Fibrosis

Treat with prednisolone and azathioprine

Question 16

Spotty necrosis

Answer 16

Look for focal aggregates of neutrophils in hepatic parenchyma

Common finding in liver disease outbreaks - check herd mates